// NOTE: it is recommended to use this even if you don't understand the // following code. #include <bits/stdc++.h> #pragma GCC optimize("O3,unroll-loops") using namespace std; const long long mod=1e9+7; struct nd{ long long d, x; vector<long long>sus; vector<long long>flag; }; int main() { #define int long long ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); int N, Q; cin >> N; int d=sqrt(N); vector<long long>dp(N); vector<nd>t(N); for (int a,b,i=0;i<N;i++){ cin >> a >> b; t[i].d=a; t[i].x=min(N,b); t[i].sus.resize(d); } dp[0]=1; long long sum=0; for (int i=0;i<N;i++){ for (int j=0;j<d;j++){ dp[i]+=t[i].sus[j]; dp[i]%=mod; } if (t[i].d>=d){ int j=i; j+=t[i].d; int s=1; while (j<N&&s<=t[i].x){ dp[j]+=dp[i]; dp[j]%=mod; j+=t[i].d; s++; } } else{ if (i+t[i].d*t[i].x<N){ t[i+t[i].d*t[i].x].flag.push_back(i); } t[i].sus[t[i].d]+=dp[i]; t[i].sus[t[i].d]%=mod; } for (auto u:t[i].flag){ t[i].sus[t[u].d]-=dp[u]; t[i].sus[t[u].d]+=mod; t[i].sus[t[u].d]%=mod; } if (i!=N-1){ t[i+1].sus=t[i].sus; } sum+=dp[i]; sum%=mod; } //for (int i=0;i<N;i++) cout << dp[i] << " "; cout << endl; cout << sum; return 0; } return 0; }

Main.cpp:63:3: error: expected unqualified-id before 'return'
   63 | } return 0;
      |   ^~~~~~
Main.cpp:64:1: error: expected declaration before '}' token
   64 | }
      | ^